tzei

Built in silencer or arctic insulation?

There are two different length of levers (that i know of). One is 25.5 mm (c to c) and other is 27.5 mm (c to c). So maybe your rebuilt unit have wrong one and it doesn't close fully when everything is connected?

What is the tilt of that engine when this occurs? If that's correct then there has to be some crud in oil gallery before it leads under 2nd and 3rd head oil drain holes before there is that downward section (beside 4th cyl.).

Flush. +1 mm valves are used in n/a race engines (if rules allow). And to make use of them you'll need cam, comp and yadda yadda... but this you already knew right.

Imo no. If alignment is correct. If not then you don’t need dyno session to smoke it.

Get a machine shop do the oil grooves.

Maybe something like this does a better job: http://www.agarscientific.com/ultrasonic-cleaner-solution-for-brass-copper-and-aluminium Google "ultrasonic cleaning solution for aluminium". There is plenty of topics.

Yes ultrasonic cleaning. Dunno about cheap ones but ones that's used in industry/laboratories should do the trick. Doubt that your local car wash got one but might give them a call What Hz's and solvents have you tried?

A sonic wash takes care of that.

How is axle carrier outer ends supports made? I can't see from pic OE push rods #33333428125.

How are your propshaft & cross joints? You want to try with known good diff.

Check all end every coolant hose that they are a) tightly clamped and b) not hardened as they may leak. Also check that water pump is not leaking (from gasket & little hole under housing). Check radiator cap gasket too. Radiator and heater core could leak also.

About 41000 miles since 2006.

my diagram (TI typical) shows that 1) these two ends connects so it is blue-green all the way to that junction (X). There is that cab in "North America typical" diagram).

Or you could use a plate #11411263218.